title: Co-receptor and accessory regulation of B-cell antigen receptor signal transduction.
abstract: The development and function of the immune system is precisely regulated to assure the generation of protective immune responses while avoiding autoimmunity. This regulation is accomplished by the engagement of a multitude of cell-surface receptors which transduce signals that activate or regulate cell differentiative and proliferative pathways. In some cases biologic responses reflect the integration of signals generated by co-aggregation of multiple receptors by complex ligands. For example, B-cell responses to antigen receptor aggregation can be modulated by co-aggregation of receptors for immunoglobulin G (Fc gamma RIIB1), complement components (CR2), and alpha 2, 6-sialoglycoproteins (CD22). Here we review our recent studies of molecular mechanisms underlying co-receptor modulation of B-cell antigen receptor signaling. Our results define interesting circuitry involving interactions among the B-cell antigen receptor, CD19 and Fc gamma RIIB1. CD19 may function as an important integrator of positive and negative signals that regulate B-cell antigen receptor signal output.
authors.affiliation: Department of Pediatrics, National Jewish Medical and Research Center, Denver, Colorado 80206, USA.
authors.forename: A M
authors.initials: AM
authors.lastname: Buhl
authors.forename: J C
authors.initials: JC
authors.lastname: Cambier
mesh_terms: D000818:Animals; D015703:Antigens, CD / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology*; D006801:Humans; D010744:Phosphoric Monoester Hydrolases / Q000378:metabolism; D011947:Receptors, Antigen, B-Cell / Q000276:immunology*; D017452:Receptors, IgG / Q000276:immunology; D015398:Signal Transduction / Q000276:immunology*
chemical_list: D015703:Antigens, CD; C080571:Fc gamma receptor IIB; D011947:Receptors, Antigen, B-Cell; D017452:Receptors, IgG; D010744:Phosphoric Monoester Hydrolases